SAN DIEGO – Smugglers are buying puppies at rock-bottom prices in Mexico and selling them in the United States for up to $1,000, often to animal lovers who later discover the canines are too sick or too young to survive on their own, authorities said Tuesday.

The Border Puppy Task Force – a group of 18 animal-control and health agencies and animal-protection groups – said a two-week operation at San Diego’s two border crossings confirmed what they long suspected: Mexico is a breeding ground for unscrupulous puppy peddlers.

“It’s a profit-driven practice, it’s a disturbing practice,” said Capt. Aaron Reyes, director of operations at the Southeast Area Animal Control Authority in Los Angeles County.

From Dec. 5 through Sunday, agents at the San Ysidro and Otay Mesa border crossings ordered vehicles carrying anything with “feathers, fleas, fur or fangs” to a separate area for more thorough inspections, Reyes said.

The vehicle searches turned up 362 puppies under 3 months old, 155 between 3 and 6 months and 1,061 adult dogs. Smuggled canines were found in trunks and under seats.

It’s unclear exactly how many of those dogs were on their way to market – it’s legal to ferry dogs if they are declared at the border and they have rabies shots and health records – but Reyes said most of those up to 6 months old were likely transported to be sold.

The puppies – typically small breeds like poodles and Chihuahuas – are believed to be purchased in Mexico for between $50 and $150, then sold at street corners, parking lots and flea markets in Southern California for between $300 and $1,000 each.

The Border Puppy Task Force formed last year after a spate of complaints from brokenhearted owners who reported their dogs were turning sick and often dying. They were getting socked with thousands of dollars in veterinarian bills. Common diseases include distemper, rabies and parvovirus.

No arrests were made during the two weeks of inspections at the San Diego border crossings. Authorities described the operation as a “census” to measure how many dogs were being smuggled across the border.